The mid-term outcome of primary open valvotomy for critical aortic stenosis in early infancy - a retrospective single center study over 18 years.

BACKGROUND: The objective of this study was to examine early and long-term results of surgical aortic valvotomy in neonates and infants aged less than four months and to identify predictors of outcome. METHODS: Between August 1994 and April 2012, 83 consecutive patients younger than 4 months of age underwent open heart valvotomy for critical aortic stenosis in our institution. Median age was 17 days (range 0-111 days). We examined clinical records to establish determinants of outcome and illustrate long-term results. RESULTS: Fifty-six patients (67 %) were neonates. Associated cardiac malformations were found in 24 patients (29 %), including multilevel left heart obstruction in 5. The median follow-up was 4.2 years. The time-related survival rate was 87 and 85 % at 5 and 15 years, respectively. The time-related survival without reintervention was respectively 51, 35 and 18 % at 5, 10 and 15 years. The time-related survival without aortic valve replacement was respectively 67, 54 and 39 % at 5, 10 and 15 years. Ventricular dysfunction (p = 0.04), delayed sternal closure (p = 0.007), endocardial fibroelastosis (p = 0.02) and low z-score of the aortic annulus (p = 0.04) were found predictors of global mortality. Ventricular dysfunction (p = 0.01) and endocardial fibroelastosis (p = 0.04) were found predictors of reintervention. CONCLUSIONS: The experience, in our center, on the management of critical aortic stenosis, shows a low early and late mortality, but the aortic valvotomy is a palliative procedure and we see unfortunately a high rate of reintervention among which the aortic valve replacement. These results suggest to reconsider the use of aortic balloon valvotomy, and particularly for the neonates with a low cardiac output in order to avoid the myocardial stress and the neurological injury due to the cardiopulmonary bypass.

Long-term outcomes of the arterial switch operation for transposition of the great arteries and ventricular septal defect and/or aortic arch obstruction.

OBJECTIVES: Long-term outcomes after the arterial switch operation (ASO) for complex transposition of the great arteries (TGA) should be clarified. METHODS: A retrospective study was conducted in patients operated on between 1982 and 1998. Overall 220 postoperative survivors, 79.1% with a ventricular septal defect, 13.2% with multiple ventricular septal defects, and 29.1% with aortic arch obstruction, were followed for 17 years (0-28 years). RESULTS: The conditional survival rate was 96.7% [95% confidence interval (CI): 94.4-99.1] at 25 years. Late sudden death occurred in 2 asymptomatic patients. The cumulative incidence rate of death or reinterventions was 3.8% (95% CI: 2.9-4.8) at 25 years, with age at ASO <10 days and aortic regurgitation at discharge identified as independent risk factors. The cumulative incidence rate of neoaortic regurgitation was 41.6% (95% CI: 20.5-62.8) at 25 years with an aorto-pulmonary diameter mismatch at the time of the ASO, age at ASO <10 days and aortic regurgitation at discharge identified as independent risk factors. At the last follow-up, 53 patients (24.1%) had neoaortic root dilatation with an aortic sinus z-score ≥3 and 6 of them had a Bentall operation at a median delay of 14.1 years since the ASO. The only independent factors for neoaortic root dilatation were male sex and an aorto-pulmonary diameter mismatch at the time of the ASO. CONCLUSIONS: Despite a continual rate of reinterventions, long-term survival and cardiovascular outcome are excellent after ASO for complex TGA. Dilatation of the neoaortic root and neoaortic regurgitation may be observed with time and 2 late sudden deaths occurred, justifying a close follow-up in all patients.

Subaortic Area at Risk for Development of Obstruction After Surgical Repair of Atrioventricular Septal Defect: Myth or Reality?

BACKGROUND: Morphology of the left ventricular outflow tract (LVOT) in atrioventricular septal defects (AVSDs) has been reported to be at risk for development of obstruction. The purpose of the present study was to identify the incidence, the risk factors, and the surgical outcomes of subaortic stenosis in repaired AVSDs. METHODS: Records of 427 consecutive patients who underwent anatomical repair for all types of AVSDs from January 2000 to December 2012 were reviewed. Outcomes, independent risk factors, reoperation, and death were analyzed. RESULTS: In a median follow-up of five years (range: 17 months-11.8 years), eight patients required nine reoperations for subaortic stenosis. Study group (n = 11) included three additional patients for whom repair was performed in a different institution. Median delay for reoperation was 11.9 years (range: 1.3-19.4 years). Surgical relief of subaortic stenosis was obtained by means of the enlargement of the LVOT: resection of fibrous structures in all reoperated patients and associated with septal myectomy in four. Two patients required a modified Konno procedure. Five reoperations were associated with left atrioventricular valve repair or replacement. Statistical analysis didn't reveal any morphologic or demographic risk factors. No early or late death occurred. CONCLUSION: The development of subaortic stenosis after repair of AVSD remains a rare complication in midterm follow-up (incidence: 1.9%). The performance of preventive gesture during repair seemed to be unjustified. The surgical management of this reoperation consists of a simple and safe procedure.

Critical Congenital Heart Diseases in Preterm Neonates: Is Early Cardiac Surgery Quite Reasonable?

Prematurity is a recognized risk factor for morbidity and mortality following cardiac surgery. Postoperative and long-term outcomes after cardiac surgery performed in the preterm period are poorly described. The aim of this study was to analyze a population of preterm neonates operated on for critical congenital heart disease (CHD) before 37 weeks of gestational age (wGA) with special attention given to early and late mortality and morbidity. Between 2000 and 2013, 28 preterm neonates (median gestational age (GA) 34.3 weeks) underwent cardiopulmonary bypass (CPB) surgery for critical CHD before 37 wGA; records were retrospectively reviewed. All patients except three with single ventricle physiology had a single-stage anatomic repair. Overall mortality was 43 % (95 % CI 25-62). Risk factors for death were birth weight (p = 0.032) and weight at surgery (p = 0.037), independently of GA, preoperative status, CPB and aortic clamp time. Seven patients, including those with univentricular hearts, died during the postoperative period, and five in the first year after surgery. Median follow-up was 5.9 years (range 1 month-12.8 years). Kaplan-Meier survival rate was 75 % (95 % CI 59-91) at 1 month, and 57 % (95 % CI 39-75) at 1 and 5 years. Eight patients required reoperations after a delay of 2.8 ± 1.3 months; eight had bronchopulmonary dysplasia. At the end of follow-up, nine patients were asymptomatic. One-stage biventricular repair for critical CHD on preterm neonates was feasible. Mortality remained high but acceptable, mainly confined to the first postoperative year and related to small weight. Despite reoperations, long-term clinical status was good in most survivors. Further long-term prospective investigations are necessary to evaluate neurodevelopmental outcomes.

Right ventricular failure secondary to chronic overload in congenital heart diseases: benefits of cell therapy using human embryonic stem cell-derived cardiac progenitors.

OBJECTIVE: Despite the increasing incidence of right ventricular (RV) failure in adult patients with congenital heart disease, current therapeutic options are still limited. By contrast to left-heart diseases, cell-based myocardial regeneration applied to the right ventricle is poorly studied, even though it may be a therapeutic solution. As human embryonic stem cell-derived cardiac progenitors seem to be good candidates owing to their proliferation capacity, our aim was to assess, in a large animal model of overloaded RV dysfunction, the feasibility and effects of such a cell therapy. METHODS: Human MesP1(+)/SSEA-1(+) cardiogenic mesodermal cells were administered using multiple intramyocardial injections 4 months after a surgical procedure mimicking the repaired tetralogy of Fallot, and their effects were observed 3 months later on hemodynamic, rhythmic, and histologic parameters. RESULTS: All pigs (sham n = 6, treated n = 6) survived without complication, and cell therapy was clinically well tolerated. Although functional, contractility, and energetics parameters evolved similarly in both groups, benefits regarding arrhythmic susceptibility were observed in the treated group, associated with a significant decrease of peri-myocyte fibrosis (5.71% ± 2.49% vs 12.12% ± 1.85%; P < .01) without interstitial fibrosis change (5.18% ± 0.81% vs 5.49% ± 1.01%). Such a decrease could be related to paracrine effects, as no human cells could be detected within the myocardium. CONCLUSIONS: Cell therapy using intramyocardial injections of human MesP1(+)/SSEA-1(+) cardiogenic mesodermal cells seems to have benefits regarding overloaded RV tissue remodeling and arrhythmic susceptibility, but this mode of administration is not sufficient to obtain a significant improvement in RV function.

Late outcomes after arterial switch operation for Taussig-Bing anomaly.

OBJECTIVE: To assess the long-term results of the arterial switch operation (ASO) for Taussig-Bing Anomaly (TBA) and identify risk factors affecting outcomes. METHODS: Retrospective review and late follow-up was performed for all TBA patients from 1997 to 2010 (follow-up >3 years). Selection criteria included the absence of mitro-pulmonary continuity. RESULTS: Sixty-nine children underwent ASO at a median age of 24 days (interquartile range [IR] 11-125), with concomitant repair of aortic arch obstruction in 26 (37.7%). Complex coronary anatomy (n = 38; 55.0%) was common. Nine (13.0%) patients had staged repair. Hospital mortality was 5.8% (95% confidence interval [CI], 1.6%-14.2%; n = 4). Median follow-up was 11.2 years (IR 7.2-13.8). Subsequent mortality was confined to the first postoperative year (n = 5, 86% [95% CI, 78%-95%]), 1-, and 10-year survival). Overall mortality was related to coronary pattern (Yacoub types C and E vs A and D, multivariate, hazard ratio [HR] 12.2 [95% CI, 1.2-122.1], P = .03). At latest follow-up, 96% of the survivors are asymptomatic, with normal ventricular function. Cumulative incidence of reintervention at 10 years was 53% (95% CI, 28%-77%). Concomitant aortic arch obstruction was a predictor of reintervention (multivariate, HR 2.9 [95% CI, 1.1-7.4], P = .03). No mortality occurred upon reinterventions. CONCLUSIONS: In the largest series to date of ASO for TBA, mortality is confined to the first postoperative year, and related to coronary artery pattern. Beyond the first year, needed reinterventions are frequent, but with sustained functional status and no mortality over >10 years follow-up. Aortic arch obstruction is the main predictor for reintervention. Despite a significant rate of early events, favorable long-term outcomes argue for use of the ASO in TBA patients.

The modified Fontan procedure with use of extracardiac conduit in adults: analysis of 32 consecutive patients.

BACKGROUND: Uncommonly, adults with functionally univentricular hearts are becoming candidates for a Fontan procedure. The purpose of this study was to evaluate the course of patients undergoing the modified Fontan procedure with an extracardiac conduit in recent years. METHODS: Between January 2003 and December 2013, 32 adult patients (17 female and 15 male) underwent total cavopulmonary connection (TCPC) with extracardiac conduit. The median age at procedure was 24.5 years (interquartile range [IQR] 20 to 33 years). The diagnoses included double-inlet left ventricle (DILV) in 10 patients (31.2%), tricuspid atresia in 8 patients (25%), double-outlet right ventricle in 4 patients (12.5%), heterotaxia in 4 patients (12.5%), and mitral atresia in 2 patients (6.2%). Seventy-eight percent of patients had undergone at least one prior palliative procedure; the most common procedures were Blalock-Taussig shunt (16 patients), superior cavopulmonary shunt (12 patients), and pulmonary artery banding (6 patients). All patients underwent cardiac catheterization preoperatively. Aortic cross-clamping was necessary in 15 patients for intracardiac procedures. Fenestration was required in 9 patients (28%). Four concomitant intraoperative cryoablation procedures were performed. RESULTS: There was no hospital mortality. One patient (3.1%) died 6 months after undergoing TCPC. Morbidities included prolonged pleural effusion lasting more than 7 days in 20 patients (62.5%), atrial arrhythmias in 4 patients (12.5%), and permanent pacemakers in 3 patients (9.3%). The median follow-up time was 33 months (interquartile range [IQR], 10.5 to 50 months). Actuarial survival was 91.83% (95% confidence limits, 71.07 to 97.89) at 1 year and 5 years. Ninety-two percent of patients were in New York Heart Association class I or II at follow-up. The median postoperative oxygen saturation was 95% (IQR, 93% to 95.5%). Cardiac arrhythmia occurred in 4 patients. Systolic ventricular function improved during follow-up for all patients except 1 patient, who underwent cardiac transplantation 7 months after the TCPC. CONCLUSIONS: The modified Fontan procedure with use of an extracardiac conduit can be performed in adults with encouraging early and midterm results. The majority of late survivors had improved quality of life. The incidence of late death, reoperation, arrhythmias, and thromboembolic events was low during follow-up.

Mitral disease: the real burden for Ross-Konno procedure in children.

BACKGROUND: Aortic valve replacement and management of complex left ventricular outflow tract obstruction in early life remains a surgical challenge. We assessed our experience with the Ross-Konno procedure. METHODS: Since 2000, 49 consecutive patients (24 neonates and infants) underwent the Ross-Konno procedure. Anatomic and clinical risk factors were analyzed. RESULTS: Median age was 12.2 months (0.0 to 194.4); 82% had previous valvotomy (surgical, n = 26; balloon, n = 7; balloon then surgical, n = 7) and 35% preceding arch repair (n = 17). Fifteen patients (31%) required concomitant procedures: mitral valve repair (n = 11), replacement (n = 1), endocardial fibroelastosis resection (n = 4), and aortic arch repair (n = 2). There were 5 hospital deaths (10.2%). Median follow-up was 63 ± 47 months. There were 4 late deaths (8.1%), all because of persistent pulmonary hypertension despite subsequent mitral procedures. Five-year actuarial survival and freedom from reoperation were 79.7% ± 6.1% and 68.6% ± 9.3%, respectively. Preoperative lower shortening fraction (p = 0.005) was associated with early mortality, while concomitant mitral surgery and pulmonary hypertension (p = 0.002) were associated with late mortality. Sixteen patients underwent 26 reoperations. Autograft function was normal in 30 of the 37 late survivors (81.1%), 4 (10.8%) had grade 2 regurgitation, and 3 (8.1%) required valve replacement. CONCLUSIONS: Ross-Konno in children remains a high-risk procedure. Preoperative ventricular dysfunction is associated with significant early mortality and should favor conservative options. Mitral involvement substantially affects late outcome, survival for these patients relies on the efficacy in relieving mitral disease. Efforts to improve mitral repair in these infants are critically required as an alternative to univentricular pathways.

Reoperations for left atrioventricular valve dysfunction after repair of atrioventricular septal defect.

OBJECTIVES: Postoperative left atrioventricular valve (LAVV) dysfunction is known to be the principal risk factor influencing outcome after repair of all types of atrioventricular septal defect (AVSD). The purpose of the present study was to identify the risk factors for reoperation and to assess the outcomes after reoperation for LAVV dysfunction. METHODS: Records of 412 patients who underwent anatomical repair for different types of AVSD from January 2000 to July 2012 were reviewed. The study group (n = 60) included 13 additional patients for whom repair ± LAVV reoperation was performed in a primary institution. Outcomes, independent risk factors, reoperation and death were analysed. RESULTS: There were 7 early, (1.7%) and 1 late death. Forty-seven (11.4%) required 64 reoperations for LAVV dysfunction. The median delay for the first LAVV reoperation was 3.5 months (range: 5 days to 10.0 years). Unbalanced ventricles with small left ventricle [odds ratio (OR) = 4.06, 95% confidence interval (CI): 1.58-10.44, P = 0.004], double-orifice LAVV (OR = 5.04, 95% CI: 1.39-18.27, P = 0.014), prior palliative surgery (OR = 3.5, 95% CI: 1.14-10.8, P = 0.029) and discharge echocardiography documenting LAVV regurgitation grade >2 (OR = 21.96, 95% CI: 8.91-54.09, P < 0.001) were found to be independent risk factors for LAVV reoperation. Twelve-year survival and freedom from LAVV reoperation rates were, respectively, 96.1% (95% CI: 94.1-98.1) and 85.8% (95% CI: 81.3-90.3). Survival was significantly worse in patients who underwent LAVV reoperation (P < 0.001) and in those who underwent valve replacement vs valve repair (P = 0.020). CONCLUSION: After AVSD repair, LAVV dysfunction appears to be the principal factor that influences outcome. It can usually be managed by repair. Need for multiple reoperations is not uncommon. Long-term outcome in patients with repaired LAVV is favourable.

Electrical velocimetry as a tool for measuring cardiac output in small infants after heart surgery.

PURPOSE: Cardiac output (CO), the product of stroke volume (SV) and heart rate, is essential to guarantee organ perfusion, especially in the intensive care setting. As invasive measurement of CO bears the risk of complications there is a need for non-invasive alternatives. We investigated if electrical velocimetry (EV) and transthoracic Doppler (Doppler-TTE) are interchangeable for the non-invasive measurement of SV and able to reflect the post-surgical SV/CO trend. METHODS: Comparison of SV measurements by EV and Doppler-TTE was performed in 24 newborns after switch operation (n = 240 measurements). Three subgroups of measurements (=periods) were created according to the patients' status in the course of post-surgical CO recovery. RESULTS: Bland-Altman analysis found acceptable bias and limits of agreement for the interchangeability of the two methods. Mean overall SV was 3.7 ml with a mean overall bias of 0.28 ml (=7.6 %). The mean percentage error of 29 % was acceptable according to the method of Critchley and Critchley. Overall precision expressed by the coefficient of variation (CV) was 6.6 % for SV(TTE) and 4.4 % for SV(EV). SV(TTE) and SV(EV) medians in the three periods were significantly different and documented the post-surgical CO trend. CONCLUSIONS: EV and Doppler-TTE are interchangeable for estimating SV. EV has the advantages of easy handling and allows continuous measurement.

Continuous cerebral perfusion for aortic arch repair: hypothermia versus normothermia.

BACKGROUND: Deep hypothermia with circulatory arrest (CA) is routinely used for aortic arch repair. Antegrade selective cerebral perfusion (ASCP) has been proposed to avoid neurologic complications. The optimal temperature during aortic arch repair with ASCP is not well established. We therefore compared early outcomes of patients undergoing aortic arch repair associated with intracardiac repair with ASCP either with hypothermia (<28°C, group I; n=70) or normothermia (>34°C, group II; n=40). METHODS: From 2002 to 2008, 110 consecutive patients with interrupted aortic arch (n=40) or coarctation of the aorta (n=70) and cardiac anomalies underwent intracardiac and aortic arch repair without CA. Median age at repair was 12 days. Full cardiopulmonary bypass (CPB), high hematocrit, and high rates of flow were used. ASCP flow was adjusted to maintain arterial pressure at greater than or equal to 50 mm Hg. ASCP was achieved either through a Gore-Tex (W. L. Gore & Associates, Inc., Elkton, MD) graft to the innominate artery (n=36) or by direct cannulation (n=74). An electroencephalogram (EEG) was continuously monitored and 30 patients were monitored by near-infrared spectroscopy (NIRS). RESULTS: Preoperative data were similar in both groups. Group II demonstrated higher ASCP flows (p<0.001). Time to extubation, stay in the intensive care unit (ICU), and postoperative urine output and lactate levels were similar between groups. Mortality was 8.5% in group I versus 10% in group II. During the postoperative course, there were no clinical or electrical neurologic events in either group. CONCLUSIONS: Antegrade selective cerebral perfusion can safely avoid CA. No worse, early, or long-term effects of ASCP with normothermia were found.

Surgical management of congenital heart defects associated with heterotaxy syndrome.

OBJECTIVE: Heterotaxy syndrome (HS) is generally associated with complex congenital cardiac defects and has a high morbidity and mortality despite recent surgical progress. Only few reports deal with an overall surgical population. METHODS: Between 1989 and 2008, 139 patients with HS entered a programme of surgical repair. Fifty-one patients were suitable for univentricular heart repair (UVR) and 88 for biventricular repair (BVR). Among those tracked for UVR, two were switched to BVR and 11 from BVR to UVR. Median age at first surgery was 4.4 months (range: 3 days to 43 years] of whom 34 were neonates. The mean number of surgical procedure per patient was 1.99. Primary BVR was performed in 37 patients. Re-operation was required in 22 patients, 15 after BVR and seven after UVR (p>0.05). RESULTS: The overall mortality was 20.8%. It was 7.2% after the first surgery, 6.6% after the second and 11.5% after the third. The overall mortality in patients with univentricular physiology was 25.5% and 18.2% in the biventricular group (p<0.05). According to the surgical track, in the UVR group, mortality was 18% and 15.6% in the BVR group (p=NS). This rate was 40% in patients with long-lasting palliation (p<0.05 vs both other groups). Median follow-up was 127 months (range: 1 month to 19 years). The overall survival rate at 15 years was 70.6%. When considering ventricular anatomy, survival rates at 15 years were 69% for the univentricular group and 74.2% for the biventricular group (p>0.05). According to the type of surgical approach, at 15 years they were 85.1% for UVR and 77% for BVR (p=NS). For the palliation group, it was 15% only at 15 years (p<0.05 vs both other groups). Risk factors for overall mortality were neonatal surgery, long-standing palliation, total anomalous pulmonary vein return (TAPVR) and right ventricular outflow tract obstruction (RVOTO). At the last visit, all survivors were in the New York Heart Association (NYHA) class I to II and only two presented with supraventricular arrhythmias. CONCLUSIONS: HS remains a difficult situation with high morbidity and mortality. An aggressive approach to repair TAPVR when present should be considered. Early decision to track the patient in either uni- or biventricular repair programme should avoid long-lasting deleterious palliation.

Right ventricular failure secondary to chronic overload in congenital heart disease: an experimental model for therapeutic innovation.

OBJECTIVE: Mortality and morbidity related to right ventricular failure remain a problem for the long-term outcome of congenital heart diseases. Therapeutic innovation requires establishing an animal model reproducing right ventricular dysfunction secondary to chronic pressure-volume overload. METHODS: Right ventricular tract enlargement by transvalvular patch and pulmonary artery banding were created in 2-month-old piglets (n = 6) to mimic repaired tetralogy of Fallot. Age-matched piglets were used as controls (n = 5). Right ventricular function was evaluated at baseline and 3 and 4 months of follow-up by hemodynamic parameters and electrocardiography. Right ventricular tissue remodeling was characterized using cellular electrophysiologic and histologic analyses. RESULTS: Four months after surgery, right ventricular peak pressure increased to 75% of systemic pressure and pulmonary regurgitation significantly progressed, end-systolic and end-diastolic volumes significantly increased, and efficient ejection fraction significantly decreased compared with controls. At 3 months, the slope of the end-systolic pressure-volume relationship was significantly elevated compared with baseline and controls; a significant rightward shift of the slope, returning to the baseline value, was observed at 4 months, whereas stroke work progressed at each step and was significantly higher than in controls. Four months after surgery, QRS duration was significantly prolonged as action potential duration. Significant fibrosis and myocyte hypertrophy without myolysis and inflammation were observed in the operated group at 4 months. CONCLUSION: Various aspects of early right ventricular remodeling were analyzed in this model. This model reproduced evolving right ventricular alterations secondary to chronic volumetric and barometric overload, as observed in repaired tetralogy of Fallot with usual sequelae, and can be used for therapeutic innovation.

Variability of bronchial measurements obtained by sequential CT using two computer-based methods.

This study aimed to evaluate the variability of lumen (LA) and wall area (WA) measurements obtained on two successive MDCT acquisitions using energy-driven contour estimation (EDCE) and full width at half maximum (FWHM) approaches. Both methods were applied to a database of segmental and subsegmental bronchi with LA > 4 mm(2) containing 42 bronchial segments of 10 successive slices that best matched on each acquisition. For both methods, the 95% confidence interval between repeated MDCT was between -1.59 and 1.5 mm(2) for LA, and -3.31 and 2.96 mm(2) for WA. The values of the coefficient of measurement variation (CV(10), i.e., percentage ratio of the standard deviation obtained from the 10 successive slices to their mean value) were strongly correlated between repeated MDCT data acquisitions (r > 0.72; p < 0.0001). Compared with FWHM, LA values obtained using EDCE were higher for LA < 15 mm(2), whereas WA values were lower for bronchi with WA < 13 mm(2); no systematic EDCE underestimation or overestimation was observed for thicker-walled bronchi. In conclusion, variability between CT examinations and assessment techniques may impair measurements. Therefore, new parameters such as CV(10) need to be investigated to study bronchial remodeling. Finally, EDCE and FWHM are not interchangeable in longitudinal studies.

Non-invasive diagnosis of ischaemic heart failure using 64-slice computed tomography.

AIMS: We evaluated the accuracy of 64-slice computed tomography (CT) to identify ischaemic aetiology of heart failure (IHF). METHODS AND RESULTS: Ninety-three consecutive patients in sinus rhythm with dilated cardiomyopathy but without suspicion of coronary artery disease (CAD) were enrolled when admitted for angiography. Accuracy of CT to detect significant stenosis (>50% lumen narrowing) was compared with quantitative coronary angiography. IHF was defined as a significant stenosis on left main or proximal left anterior descending artery or two or more vessels. Forty-three out of 1395 segments (3%) were heavily calcified and excluded. CT correctly assessed 103 of 142 (73%) significant stenosis and identified 46 of 50 (92%) patients without and 42 of 43 (98%) patients with CAD, 60 of 62 (97%) patients without and 28 of 31 (90%) patients with IHF. Overall, accuracy, sensitivity, specificity, positive predictive value, and negative predictive value of CT for identifying CAD by segment was 96, 73, 99, 92, and 97%, respectively; by patient was 95, 98, 92, 91, and 98%, respectively; and for identifying IHF was 95, 90, 97, 93, and 95%, respectively. CONCLUSION: Non-invasive 64-slice CT assessment of the extent of CAD may offer a valid alternative to angiography for the diagnosis of IHF.

Fate of the truncal valve in truncus arteriosus.

BACKGROUND: The fate of the truncal valve (TV) after truncus arteriosus repair remains poorly defined. The purpose of this report was to analyze how the TV influences outcome of truncus arteriosus repair. METHODS: From January 1986 to December 2003, 153 patients underwent complete repair of the truncus arteriosus. Median age was 35 days. Preoperative TV insufficiency was absent or trivial in 59 patients (39%), mild in 72 patients (47%), moderate in 13 patients (8%), and severe in 9 patients (6%). The TV was quadricuspid in 36 patients (24 %), bicuspid in 10 patients (7%), and tricuspid in the remaining patients. At surgery, TV plasty (n = 6) or replacement (n = 3) was associated with truncus arteriosus repair. Truncal valve-aorta continuity was restored by patch interposition in 27 patients (17%), by conduit in 7 patients (5%), and directly in the remaining patients. RESULTS: A 97-month mean follow-up was achieved in all survivors. The actuarial survival rates were 81.7% +/- 3.1% and 79.1% +/- 3.3% at 6 months and 18 years, respectively. Among 85 patients who underwent 113 reoperations, 19 underwent 24 TV reoperations: 5 isolated TV reinterventions and 19 associated with right ventricular-pulmonary artery conduit replacement. Freedom from TV reoperation was 96%, 82.3%, and 62.7% at 1, 10, and 18 years, respectively. Multivariate logistic regression showed that moderate or severe TV insufficiency at initial presentation was a risk factor for late TV reoperation but not for early mortality. Initial TV replacement was associated with lower survival. CONCLUSIONS: Initial TV insufficiency is associated with higher reoperation rate. This condition requires more refined techniques of TV plasty. The overall long-term freedom of TV reintervention rate remains within reasonable ranges. Truncal valve reintervention presents a low risk for mortality.

Comparison of 64-slice computed tomography planimetry and Doppler echocardiography in the assessment of aortic valve stenosis.

BACKGROUND AND AIM OF THE STUDY: The study aim was to compare, prospectively, the planimetry of aortic stenosis on 64-slice computed tomography (CT), with the area calculated by Doppler transthoracic echocardiography (TTE) in symptomatic patients evaluated before potential aortic valve replacement. METHODS: Fifty-two consecutive patients (27 males, 25 females; mean age 74 +/- 10 years) admitted to the authors' institution during 2005 were evaluated with 64-slice CT and Doppler TTE. The time interval between the two evaluations was 2 +/- 1 weeks. Planimetry of the anatomic orifice area (AOA) drawn on 64-slice CT was compared to the effective area determined by Doppler TTE by Bland and Altman analysis, and the anatomic area threshold value corresponding to a significant effective aortic stenosis (50.75 cm2) was determined by receiver operating characteristic (ROC) analysis. RESULTS: The aortic orifice area measured by 64-slice CT correlated well with the effective area (r = 0.76; p <0.0001), but was significantly greater, with a systematic overestimation (0.132 cm(2)) and a variability of 0.239 cm(2). There was good agreement between planimetry determined by two independent radiologists (difference = 0.002, variability = 0.115 cm(2)). ROC analysis showed that a threshold value of 0.95 cm(2) as measured by 64-slice CT planimetry identifies significant aortic stenosis with sensitivity, specificity, accuracy, positive and negative predictive values of 82%, 77%, 81%, 91% and 59%, respectively. CONCLUSION: 64-slice CT is a reproducible and reliable non-invasive method to evaluate aortic valve stenosis compared to the reference method of Doppler TTE. Indeed, the CT approach could replace the latter evaluation when measurements used in the continuity equation are inadequate.

Surgery for right ventricle to pulmonary artery conduit obstruction: risk factors for further reoperation.

OBJECTIVE: To identify the surgical approaches and risk factors which influence longevity of right ventricle to pulmonary artery (RV-PA) conduits following first reoperation for obstruction. METHODS: Between January 1993 and August 2003, 114 patients underwent 141 reoperations for RV-PA conduit obstruction. Diagnoses included 'Truncus Arteriosus' (n=52), 'Pulmonary atresia/Tetralogy of fallot' (n=39), 'Double outlet right ventricle' (n=10), 'Transposition of great arteries, VSD, and pulmonary atresia' (n=9), and the 'Ross operation' (n=4). All patients had undergone a previous biventricular repair. The first reoperation for conduit obstruction was performed in 112 hospital survivors by: total conduit replacement (Group A, n=73) with valved (homograft=10 and xenograft=54) or non-valved (n=9) conduit, and patch enlargement of the obstructed RV outflow tract with preservation of the posterior and sides of the conduit wall after removing of the fibrocalcific peel and degenerated valve (Group B, n=39). Mean age at first reoperation was 8.8+/-6.7 and 7.5+/-5.3 years in patients of groups A and B, respectively. Seven patients in Group A and 18 in Group B required a second reoperation and two patients in Group B a third reoperation. RESULTS: There were two hospital deaths and no late deaths. Mean follow-up was 5.8+/-3.2 years. Risk factors for second reoperation by univariate analysis were: homograft conduit use (P=0.004), Group B surgical approach (P=0.0001), higher RV-PA systolic pressure gradient at discharge (P=0.02), and age <5-years-old (P=0.01). Multivariate analysis showed that inclusion in Group B and younger age (<5-years-old) at repair were independent risk factors for second reoperation. Group B surgical approaches had higher RV-PA systolic pressure gradient at discharge (P=0.02) and required more PA bifurcation repair at the time of second reoperation (P=0.05). Freedom from second reoperation for conduit obstruction was significantly higher in Group A patients at 5 and 8 years (P<0.04) and those with xenografts rather than homograft (P=0.04). CONCLUSIONS: Our results support the optimal surgical approach for RV-PA conduit obstruction is total replacement with a xenograft. RV outflow reconstruction by other techniques without complete dissection of PA bifurcation does not completely relieve the stenosis and could cause early restenosis. Higher systolic gradients at discharge and younger age at first reoperation are predictors of earlier reoperation.

Moderate and chronic hemodynamic overload of sheep atria induces reversible cellular electrophysiologic abnormalities and atrial vulnerability.

OBJECTIVES: The aim of this study was to evaluate the myocardial consequences of a chronic volume overload of the left atrium (LA). BACKGROUND: Atrial dilation is a major risk factor for atrial fibrillation (AF), but the underlying mechanisms are poorly understood. METHODS: A left-right aorto-pulmonary artery shunt (APS) was created in sheep. The cardiopathy was characterized by echocardiography, electrophysiologic testing, and histologic analysis. Cellular action potential (AP) and calcium current (I(Ca)) were recorded by means of microelectrode and patch clamp techniques. RESULTS: Three to four months after surgery, all animals in the APS state had a dilated LA (146.2 +/- 35.4 cm(2)/m(2) vs. 91.7 +/- 10.4 cm(2)/m(2) in the control state; p = 0.0024) but remained in sinus rhythm. Repetitive atrial firing was triggered by a single extra beat in five of six animals in the APS state and in two of six animals in the control state. Moreover, in two animals in the APS state, a single extra beat triggered sustained AF. Myocytes were enlarged and 39.8% showed some degree of myolysis. In animals in the APS state, the AP had no plateau phase or small amplitude and numerous myocytes were unexcitable. The I(Ca) density was 45.2% lower in APS animals than in control animals. Beta-adrenergic stimulation normalized I(Ca) and restored the plateau phase of the AP. After shunt suppression, the electrophysiologic properties of the atria returned to normal. CONCLUSIONS: The APS induced moderate, isolated LA dilation, which was sufficient to cause major changes in cellular electrophysiologic properties and to render the atria vulnerable to fibrillation. These effects were reversed by shunt suppression.

Left-sided lesions after anatomic repair of transposition of the great arteries, ventricular septal defect, and coarctation: surgical factors.

OBJECTIVE: This study was undertaken to identify potential anatomic and surgical factors creating left-sided lesions, namely recoarctation of the aorta and neoaortic regurgitation, after anatomic repair of transposition of the great arteries with ventricular septal defect and aortic coarctation. METHODS: From 1983 to September 2002, 109 survivors out of 120 patients were studied. Two-stage repair was performed in 42 patients (group A), and single-stage repair was performed in 67 (groups B and C). Before repair, the diameters of the ascending aorta and main pulmonary artery were measured. In the patients with single-stage repair, coarctation was repaired by extended end-to-end anastomosis in 35 patients (group B) and by pulmonary homograft patch augmentation in 32 patients (group C). The ventricular septal defect was closed through the pulmonary artery in 70 patients and through the right ventricle or atrium in 39 patients. The neoaorto-aortic discrepancy was treated by V-shaped resection of the posterior sinus of Valsalva in 7 cases, pulmonary homograft patch in 32 cases, and anterior splitting of the ascending aorta in all cases. Before discharge from the hospital, neoaortic root and ascending aorta diameters and aortic regurgitation grade were recorded. Neoaortic regurgitation progression and reintervention were the end points of follow-up (97.2 +/- 61.2 months). RESULTS: Early and late survivals were significantly better in group C (P <.001). Risk factors for neoaortic regurgitation at discharge by univariate analysis were single-stage repair (P <.05) and ventricular septal defect closure through the pulmonary artery (P =.0076). On multivariate analysis, the latter was the only risk factor for neoaortic regurgitation at discharge and at last follow-up. Multivariate analysis showed that higher neoaortic root/ascending aorta ratio and ventricular septal defect closure through the pulmonary artery were risk factors for neoaortic regurgitation evolution at last follow-up. There were 29 reinterventions, 19 for recoarctation of the aorta and 10 for neoaortic regurgitation with or without aortic root dilatation. Group B (P <.05), high neoaortic root/ascending aorta ratio (P <.01), and progressive neoaortic regurgitation (P <.05) were risk factors for recoarctation of the aorta. Group A was a risk factor for aortic valve replacement at 10 years (P <.05). CONCLUSION: Neonatal single-stage repair with pulmonary homograft aortic augmentation remains the optimal approach to transposition of the great arteries with ventricular septal defect and aortic coarctation. It provides better early and late survivals and freedoms from left-sided lesions. Avoidance of late recoarctation of the aorta and progressive neoaortic regurgitation requires meticulous closure of the ventricular septal defect and evenly sized reconstruction of the aorta from root to distal arch.